To assess the efficacy of noninvasive pressure support ventilation (NPSV) using a new special helmet as first-line intervention to treat patients with hypoxemic acute respiratory failure (ARF), in comparison to NPSV using standard facial mask.
Design and Setting
Prospective clinical pilot investigation with matched control group in three intensive care units of university hospitals.
Patients and Methods
Thirty-three consecutive patients without chronic obstructive pulmonary disease and with hypoxemic ARF (defined as severe dyspnea at rest, respiratory rate >30 breaths/min, Pao2:Fio2 < 200, and active contraction of the accessory muscles of respiration) were enrolled. Each patient treated with NPSV by helmet was matched with two controls with ARF treated with NPSV via a facial mask, selected by simplified acute physiologic score II, age, Pao2/Fio2, and arterial pH at admission. Primary end points were the improvement of gas exchanges, the need for endotracheal intubation, and the complications related to NPSV.
The 33 patients and the 66 controls had similar characteristics at baseline. Both groups improved oxygenation after NPSV. Eight patients (24%) in the helmet group and 21 patients (32%) in the facial mask group (p = .3) failed NPSV and were intubated. No patients failed NPSV because of intolerance of the technique in the helmet group in comparison with 8 patients (38%) in the mask group (p = .047). Complications related to the technique (skin necrosis, gastric distension, and eye irritation) were fewer in the helmet group compared with the mask group (no patients vs. 14 patients (21%), p = .002). The helmet allowed the continuous application of NPSV for a longer period of time (p = .05). Length of stay in the intensive care unit, intensive care, and hospital mortality were not different.
NPSV by helmet successfully treated hypoxemic ARF, with better tolerance and fewer complications than facial mask NPSV.